Application Study Of Fluorescent Spectroscopy On Pesticide Residue Detection

The application of pesticide promoted the development of modernagriculture. However, along with the continuous increase of variety and quantityof the pesticide, the serial problems coursed by the pesticide residua that in thefood and environment becomes more and more outstanding, the harm to thehuman health and the environment courses widely international attention. Sohigh-sensitivity detection method becomes greatly important to the pesticideresidua and their metabolites.The fluorescent spectroscopy that has the merit of high sensitivity andselectivity, using small quantity of sample and so on, has been widely used in therelative realm. However, as the continually development of the analytical objectand the increasingly complex of the mission, traditional fluorometric analysiscan't reach the practical demand. In order to overcome the disadvantage oftraditional fluorometric analysis, using three-dimensional and derivativefluorescent spectroscopy to do the experimental research of pesticide residuadetection, also design the fluorescent spectrometer detection system. The mainresearch work is as follows:(1)Determinate the conventional fluorescence spectrum of carbamatepesticides including carbendazim, methomyl, benomyl, carbaryl and carbofuran,which in common use. Determined their optimal excitation and emissionwavelength.(2)Doing primary research of three-dimensional spectrum of carbendazim,methomyl and benomyl, make good foundation of the combination ofthree-dimensional spectrum parametrization and pattern recognition.(3)Make experiment to study the fluorescent characteristic of carbaryl andcarbofuran in different pH,use derivative fluorescent spectroscopy to scan themixed solution of them. Determine their working curve, recovery rate andprecision degree. The experimental result shows that the derivative fluorescentspectroscopy can separate the overlap fluorescence spectrum effectively,enhance the ability of fluorescent spectroscopy to measurement ofmulti-component pesticide.(4)Design fluorescence spectrometer which being used to measure pesticideresidua. Design the main part of the system such as the relative circuit of thexenon flash light source, grating monochrometer scan system, linear array CCDdetection system. Finally study the calibration of the spectrometer. This systemcan scan not only conventional fluorescence spectrum but also three-dimensionaland synchronous-derivative fluorescence spectrum. It can also make qualitativeanalysis and quantitative analysis of pesticide residua according to the data offluorescence spectrum that has been stored in the computer.